Leveraging Decoupling in Enabling Energy Aware D2D Communications

Downlink/Uplink decoupling (DUDe) in LTE net- works has caught the attention of researchers as it provides better uplink SINR and reduced power consumption per device due to decoupled connection of a device with the Macro (in downlink ) and a small cell (in uplink). These characteristics of DUDe c an be exploited to encourage more D2D communications in the network. This paper first proposes a model to estimate decoup ling region within which a device is allowed to perform DUDe. Then , it formulates an equation to calculate the total power saved by devices due to decoupling. Finally, the extra area due to decoupling which can be used to enable D2D pairs is calculate d. Simulation results are shown based on different simulation scenarios for different objectives for better understandi ng the idea proposed

Optimal placement of Femto base stations in enterprise femtocell networks

Femto cells a.k.a. Low Power Nodes (LPNs) are deployed to improve indoor data rates as well as reduce traffic load on macro Base Stations (BSs) in 4G/LTE cellular networks. Indoor UEs getting high SNR (Signal-to-Noise Ratio) can experience good throughput, but SNR decreases at faster rate due to obstacles, present along the communication path. Hence, efficient placement of Femtos in enterprise buildings is crucial to attain desirable SNR for indoor users. We consider obstacles and shadowing effects by walls and include them in the system model. We develop a Linear Programming Problem (LPP) model by converting convex constraints into linear ones and solve it using GAMS tool, to place Femtos optimally inside the building. Our extensive experimentation proves the optimal placement of Femtos achieves 14.41% and 35.95% increase in SNR of indoor UEs over random and center placement strategies, respectively

Adaptive RACH Congestion Management to Support M2M Communication in 4G LTE Networks

Machine to machine communication (M2M) or machine type communication (MTC) facilitates communication of two network enabled devices, without any human intervention, to take some intelligent decision based on the interaction of devices. Because of ubiquitous coverage and global connectivity, cellular networks are playing a major role in the deployment of M2M communications. Due to some unique characteristics of M2M communication, supporting M2M applications in cellular networks is very challenging. One of such challenge is congestion in radio access network (RAN) during RACH procedure. This is because of the fact that there are large numbers of M2M devices which access the radio network at the same time. As a solution, we propose an adaptive RACH congestion management function (ARC) which specifies congestion handling method to be used by all M2M devices based on the current congestion condition of the networ

On handovers in uplink/downlink decoupled LTE HetNets

Cellular heterogeneous networks (HetNets) are going to be one of the key enablers for 5G. Downlink/Uplink decoupling (DUDe) is a concept in which a mobile device is connected with Macro cell for downlink communication and with small cell for uplink communication in LTE/LTE-A HetNets. It improves uplink data rate, reduces power consumption of devices, balances load between Macro cell and small cells. Due to incorporation of DUDe, a mobile device has to perform separate uplink and downlink handovers unlike traditional handovers in coupled LTE networks. In this paper, we propose various handover schemes for DUDe LTE networks. Apart from this, we have mathematically analysed the received SINR by small cells taken part in decoupling, with respect to a device moving in decoupling regions of these small cells, in multiple cell interference scenario. Simulation results show the signaling impact of DUDe in handovers, increased uplink SINR, decreased power consumption of devices in both single small cell and multiple small cell scenarios

Class based priority scheduling to support Machine to Machine communications in LTE systems

Due to the ubiquitous coverage and seamless connectivity, cellular systems are very promising to support Machine-to-Machine (M2M) communications. But, all of the cellular networks are designed and optimized for Human-to-Human (H2H) or Human-to-Machine (H2M) communications and therefore facing several challenges due to incorporation of M2M communications. One of such challenges is efficient resource allocation to M2M applications without affecting or least affecting H2H applications. In order to address this challenge, we need application specific priority based scheduling algorithms in which based on the QoS of the application, radio resources are allocated. In this paper, we have classified and prioritized all H2H and M2M flows based on their QoS requirements. Resources are allocated first to higher priority classes and in a given class, they are allocated to H2H flows first. In order to ensure the QoS of H2H flows, a threshold is kept on the maximum number of radio resource blocks to be assigned to M2M flows in a scheduling interval. Performance of the proposed scheduling algorithm is evaluated using various metrics such as system throughput and average utility per class and compared against existing scheduling scheme

Class based dynamic priority scheduling for uplink to support M2M communications in LTE

Machine-to-Machine (M2M) communication has emerged as a key technology with huge market potential for cellular service providers deploying LTE networks. Addition of enormous number of M2M devices into the cellular networks poses a heavy competition to existing Human-to-Human (H2H) devices for getting radio resources, thereby affecting the performance of the H2H communications. But, one can not treat all M2M flows as low priority and schedule them after H2H flows, as there are many M2M applications like healthcare and tracking which are of high importance and delay-intolerant. Hence, there is a need for class based priority scheduling of the traffic of M2M and H2H sessions in the network. In this paper, we propose a class based dynamic priority scheduling algorithm for uplink transmission of M2M and H2H traffic in LTE. The performance of the algorithm is evaluated by various metrics such as H2H throughput and system throughput and also compared with existing scheduler